Heater



March 20, 1934.

M. A. REPLOGLE 1,951,580

HEATER Filed Sept. 7, 1928 4 Sheets-Sheet l l N VENTOR.

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A TTORNEYJ.

March 20, 1934. M REPLQGLE 1,953,580

HEATER Filed Sept. 7, 1928 4 Shegts-Sheet 2 INVENTOR. Mme/(l )TEPLATTORNEYS.

March 20, 1934.

M. A. 'REPLOGLE 1,951,580

HEATER Filed; Sept. 7, 1928 4 Sheets-Sheet 3 INVENTOR. /%7E/( ft fia wsmA TTORNE Ya March 20, 1934- M. A. REPLOGLE 1,951,58

HEATER Filed Sept. '7, 1928 4 Sheets-Sheet 4 INVENTOR, five/t 7?? 0 us ATTORNEYO',

Patented Mar. 20, 1934 PATENT OFFICE HEATER Mark A. Replogle, Akron,Ohio, assignor to The Replogle Heater Company, Akron, Ohio, acorporation of Ohio Application September '7, 1928, Serial No. 304,594

' 26 Claims.

This invention relates to heaters for domestic or industrial uses.

The general purpose of the invention is to provide a heater adapted tosecure as nearly perfect combustion of coal as is possible to attaineffective, economical heating without smoke, and this application is acontinuation-impart of prior applications Serial No. 49,763, filedAugust 12, 1925, and Serial No. 107,692, filed May 8, 1926.

Heretofore, there have been numerous attempts to provide a heater toattain the foregoing purpose, but substantially perfect and smokelesscombustion has not been produced, although some considerableimprovements in the efficiency J of coal burners has, of course, beensecured.

In order to obtain substantially complete combustion of coal, it isnecessary to produce such temperatures and to so agitate and loosen thecoking coals in a gassing pot that all of the gases,

both those ignitable at the temperatures in the gassing pot and thoseignitable at higher temperatures, the heavy as well as the light, shallbe liberated from the coal. It is also necessary to provide the rightquantity of air to burn a given amount of coal. And it is, furthermore,necessary to build up a reservoir of heat so that all the gases,including those ignitable at the higher temperatures, will burn. Thisrequires production of a temperature in the neighborhood of 2,500" to n3,000 F. at some point in the heater where the last-named gases and freeair may burn.

In all heaters heretofore employed, it has been impossible to soconserve the heat as to produce any such temperature because in allprior forms of heaters the radiation from the burning coals or gases hasbeen so great as to prevent any such temperatures being reached.

The chief objects of the present invention, therefore, are to providemeans for producing a self-perpetuating fire to which coal and air: are

suppled in the proper proportion to produce complete combustion at anydeterminate rate, to provide means for feeding the coals through thegassing pot at said rate and for keeping the coking coals thoroughlyloosened so as to liberate all the gases, and to provide means for soconserving the heat of the liberated gases as to build upa reservoir ofheat, causing ignition of these gases igniting at higher temperaturesbefore they are delivered to the radiator.

A further object of the invention is to provide means in the gassing potfor preventing the accumulation of cllnkers therein.

The foregoing and other objects are attained by the heater shown in theaccompanying-drawings and described below. It is to beunderstood thatthe invention is not limited to the specific form thereof shown anddescribed.

Of the accompanying drawings,

Figure 1 is a longitudinal section through the center of a domestic hotair heater embodying the invention;

Figure 2 is a front elevation thereof;

Figure 3 is a section on line 3-3 of Figure 1;

Figure 4; is a section on line 4-4 of Figure 1;

Figure 5 is a section on line 5-5 of Figure 1;

Figure 6 is an enlarged side elevation of the heater operatingmechanism;

Figure 6 is a detail view illustrating the pawl and ratchet whichoperates the secondary rotary drum; and

Figure 7 is an enlarged side elevation of the flue and dust boxconstruction.

Referring to the drawings, the numeral 10 designates the outer casing ofa domestic heater embodying the invention and the numeral 11 designatesthe inner casing or radiator, the air to .be heated being supplied tothe outer casing about the inner casing by means of an inlet duct 10 andbeing delivered from the heater by the ducts 12, 12 leading to thevarious rooms in a building. It is to be understood that the inventionis not limited to use in air heating systems and that other fluidheating medium may be circulated about the radiator.

The radiator casing 11 extends through the heater from the front to theback end thereof and has arranged in the lower portion thereof at thefront end a gassing pot 13 beneath which is an ash pit 14. A door 15gives access to the upper part of the radiator at the front of theheater and a door 16 gives access to the radiator at the rear of theheater. A door 17 gives access to the gassing pot and a removable coverplate 18 clamped onto an opening in the front of the ash pit to renderthe latter air tight, gives access to the ash pit.

To supply coal to the gassing pot 13, a hopper 19 is arranged at oneside of the heater to receive slack or crushed coal or coal screeningsand a conveyor 20 operating through the bottom of hopper 19 andextending through the outer casing 10 and radiator casing 11 is arrangedto feed coal into the gassing pot delivering the same atan outlet 21adjacent the top of the gassing pot. An

agitator 19 is arranged to be rotated in the hopper overthe conveyor 20so as eifectively to keep the coal flowing into the conveyor.

The supply of air to the gassing pot is preferably maintained by the useof a positive blower 22 connected by a conduit 23 to a duct 24 extendedthrough the outer and radiator casings beneath and adjacent to the coalconveyor and having an outlet 25 therefrom for delivering the air to theash pit 14. The coal conveyor and air duct are preferably provided in aunit construction mounted on a frame 26 between the gassing pot and ashpit, this frame sloping downwardly adjacent each side wall of thegassing pot forwardly of the coal and air ducts as indicated at 26 andthen extending horizontally as indicated at 26 to the front of theheater. The arrangement of the air duct under the coal conveyor ductprovides for keeping the coal cool and preventing coking thereof in theconveyor.

A coal feeding and agitating drum 27 is journaled in the gassing potbeneath the coal outlet 21 to receive the coal thereon, this drum beingof greater diameter at its center than at its sides, 1. e. of generallyconvex outer peripheral formation so that the swelling of the cokingcoals will tend to break them apart rather than to weld them togetherand so clinker up and bind the drum. The drum 2'7 is grooved as shown orotherwise irregularly formed so as both to engage the coals and feedthem through the gassing pot and to agitate the coals, keeping themloose to freely liberate their gases. The drum 2'7 is preferably made ofcarborundum, this highly refractory material being found necessary toresist the temperatures obtained in the gassing pot. Due to the drumbeing of lesser diameter at the side, the stream of fuel is moved moreslowly and tends to solidify more than at the central region of thedrum. This prevents the air passing from the bottom of the pot seekingpaths of least resistance about the sides of the fuel stream and thusmore equally distributes the air throughout the fuel stream.

In front of and spaced from drum 27 and arranged adjacent the front wallof the heater is an auxiliary agitator drum 28 of somewhat smallerdiameter, the drums providing a path therebetween for the coking coalsas they travel slowly through the gassing pot. The drum. 28 is alsopreferably carborundum.

A grate 29 is supported on frame 26 beneath the agitators, the gratebars extending from adjacent the front of the heater to a point underand, in the specific form of heater shown, slightly beyond the center ofthe feeding and agitating drum 27.

The spaces about the main and auxiliary drums and between the grate barsprovide access of air from the ash pit to the gassing pot. In addition,air outlets 30, 30 are provided along the inclined portions of frame 26on each side of the main drum 27.

It will be observed that the gassing pot construction provides formoving a stream of coal forwardly, downwardly and then rearwardly,whereby the stream is inverted in passing through the pot over thegrate.

The side walls of the gassing pot are lined with fire clay as indicatedat 31. The front wall 32 thereof is constructed as a removable sectionaccessible through door 17 and in addition has a removable plug 33therein. This wall is lined with carborundum blocks 34, this more highlyrefractory material being necessary because experience has disclosedthat the temperatures developed in the gassing pot fused fire clay andcaused it to clinker up by adhesion of coking coal particles thereto.

To provide means for producing a reservoir of heat such as necessary toburn the coal gases of high ignition points which are liberated in thegassing pot, a refractory core 35 is provided in the radiator, the corepreferably being constructed of sections which may be cemented togetherby a ceramic cement held in grooves 36, 36 and also secured together bybolts 37, 37. The front end of the core is supported on the gassing potover an opening 38111 the top thereof and provides a dome 39 for thegassing pot, this dome being lined with highly refractory material suchas carborundum blocks, the walls of the dome diverging downwardly(Figure 3) to prevent accumulation of ash or dust particles thereon. Therear end of the core is supported on the bottom of the radiator. Thecore as a whole or in sections may be removed through the rear radiatordoor.

An outlet, preferably restricted in size as compared with the area ofthe dome, is provided at 40 from the dome 39 for delivering the gases toa duct ll extending back through the core 35 downwardly to the rearthereof and then upwardly to discharge outlet slots 42, 42 through theopposite sides of the core. The duct 41 defines a secondary orsuper-combustion chamber which, because of the concentration of heatadjacent the restricted outlet 40, is partially lined with the highlyrefractory carborundum blocks 43, 43. The top surface of duct 41 isserrated or otherwise formed to provide baflies serving to thoroughlymix the combustible gases and air therein.

It will be observed that the core construction is such that the streamof gases follows a tortuous path in passing therethrough. This assistsin effecting the building up of the heat reservoir in the core and aidsin a thorough mixing of the combustible gases with the oxygen contententering the core.

A removable plug 43 is provided in the front of the core to which accessis had through door 15 and a removable plug is provided at 44 at therear and bottom of the core to which access is had through door 15,whereby the duct 41 can be easily cleaned out. An outlet 45 is providedin the bottom of the core at the rear for removal of the dust or ashcleaned from the duct, and a hinged plate 46 is arranged normally toclose this outlet.

The main flue outlet from the radiator is provided at 4"! in the bottomof the radiator at the center thereof just in back of the gassing pot,this outlet being connected by a flue duct 48 to a dust box 49 to oneside of which the flue pipe 50 is connected. An upwardly swinging door51 is provided at the rear of the dust box to give access thereto and alink 52 so connects this door with hinged plate 46 as to swing thelatter open when the dust box door is opened.

It will be observed that there is a continuous natural suction on theradiator. The flue is constructed of such dimensions as to maintain asuction of such strength as always to maintain the pressure in thegassing pot and radiator substantiallly less than atmospheric. This prevents the leakage of gases from the gassing pot or radiator into thehome and renders it unnecessary to adopt expensive expedients forpreventing gas leakage.

In order to permit starting of a fire without smoke backing up into thecellar, an auxiliary flue connection is provided to the top of theradiator at 53. This connection has a damper 54 therein operable fromthe front of the heater by a shaft 55 on which is a suitable wheel orcrank 56. This damper is closed as soon as the flue effectivelydistributed over the whole cycle. feeding action of the agitators 27 and28, thereor chimney is heated sufficiently to draw the cold air from theradiator at the start.

The mechanism for operating the various parts of the heater insynchronism at any determinate rate for regulating the temperature inthe house, includes a motor 57 slidably mounted on a base 5'? andshiftable thereon by a lever 58 which may be manually orthermostatically controlled as by connection of a cable 59 thereto whichleads to a regulator (not shown) on an upper floor.

The motor 57 has thereon a friction disc 60 for driving a friction wheel61, the disc 60 being movable to engage wheel 61 from its center to itsperiphery or vice verse by shifting of motor 5'7, whereby wheel 61 maybe driven at any desired or regulated speed.

Wheel 61 is secured on a shaft 62 which directly drives blower 22. Asprocket 63 on said shaft drives a chain 64 which in turn drives asprocket 65 secured on a shaft 66 for driving the coal feeding conveyor20. This drive may be effected through suitable worm gearing in housing6'7. The speed of conveyor 20 accordingly is synchronized with the speedof the blower and travels a slower rate, due to the speed reductiondrive shown between the two, such that the coal and air are fed indefinite proportions at any rate to which the heater is regulated,insuring complete combustion at all rates.

An eccentric 68 is mounted on the shaft of conveyor 20 which has a pinand slot connection with a crank 69 pivoted at 70 on housing 67, wherebythe latter is oscillated. A pawl '71 is secured on said crank to engagewith a ratchet wheel 72 on the shaft of the agitator 19 in the hopper toactuate the same. A pawl '72 is journaled on the eccentric 68 andengages with a ratchet wheel 73 secured on the main agitator 27 of thegassing pot for rotating the same intermittently in a clockwisedirection (Figure 1), such intermittent rotation being preferred tocontinuous rotation thereof because the intermittent movement of thisdrum tends to break up the coking coals. A pawl 74 is carried by pawl'72 to engage ratchet wheel 75 on the shaft of the auxiliary agitator 28in the gassing pot to rotate said agitator in a counter-clockwisedirection (Figure 1) It is to be noted that the three pawls '71, '72 and74 effect operation of the respective agitators over different portionsof the cycle of rotation of the conveyor 20 so that the loads are Thefore, is at such a rate as compared with the coal and air feeds that theconveying of the coking coals through the fire and the delivery of theash therefrom is maintained in proportion to the rate of combustion.

To start the operation of the heater, damper 54 is opened and a smallfire is started in the gassing pot in the usual way as by use of paper,kindling and coal, the fire being built through the front gassing potopening at 33. The cover plate 13 from the ash pit opening is removed(if it is desired) to permit natural draft through the grate. When afairly good fire is thus produced, the cover plate 18 is replaced andthe motor 57 is started, it being positioned for slow speed driving ofthe heater.

After operation in this manner for suihcient time to warm the flue 50,damper 54 is closed and the motor 56 is set to drive the heater at anydeterminate or regulated rate to produce the desired temperature in thehouse. Thereafter the fire is self-perpetuating,

The agitator 27, turning clockwise (Figure l), gradually feeds thecoking coals along a path forwardly and downwardly and then rearwardlyand delivers the ash to the ash pit, the coals being thoroughly brokenup due to its convex shape, the grooved formations on its surface andthe intermittent movementthercof. The air is positively forced up aboutthe drum 27 through the grate and through the apertures 30 along theside walls of the heater, the supply of air being in nowise affected bytemporary clogging of openings with ash because the blower builds up thepressure when this occurs and forces the air through. This causes thecoal stream to burn on both sides, on top and on the bottom, andprevents accumulation of fused ash on the side walls while at the sametime the free air cools the side walls and gradually is brought up tothe temperature for combustion of the gases liberated.

The inclined front wall 32 of the gassing pot tends to impell downwardlyany ribbon of coking coals which may tend to bridge over from theagitator 27, and agitator 28, turning counterclockwise (Figure 1),breaks up such coals and feeds them down between agitators 2'7 and 28.Air from the ash pit finds its way about the outside of the agitator 28and up along the front wall of the gassing pot, causing the front of thecoal stream to burn, cooling and preventing accumulation of fused ash onthe front wall of the gassing pot and also becoming preheated forcombustion of the gases, in the core above.

As the gases of combustion, the unburned gases and preheated air passfrom the gassing pot through the core into the radiator, they graduallyraise the dome of the gassing pot and the core, which absorbs the heat,to a high degree of temperature which is most highly concentrated at andadjacent the constricted outlet 40. This causes the gases ignitable athigher temperatures to burn. A temperature sufficient to cause ignitionof the heavier gases in the core is maintained by reason of its greatability to absorb and retain heat and also by reason of the fact thatthe gases of combustion delivered from the core are forced to passdownwardly about the core to the flue outlet 47, maintaining a lowtemperature gradient through the wall of the core and insulating thecore from the direct cooling effect of the radiating surfaces. The corebecomes first red and then white hot on its inside.

The heater, in from three to four hours, accordingly reaches a conditionin which all the gases are liberated from the coals in the gassing pot,those ignitable at lower temperatures being consumed therein and thoseignitable at higher temperatures passing along with preheated air to thecore which provides a reservoir of heat maintaining temperatures up toin the neighborhood of 2,500 to 3,000" F. and causing ignition andcomplete combustion of the heavier gases, the core passage beingsufficiently long to give the required time for complete combustion ofthe gases before emptying into the radiator.

Though the apparatus is continuously supplying fresh coal to the gassingpot, there is a complete absence of smoke in the flue, the temperaturein the core being such as to render impossible the emission of smoketherefrom.

It will be apparent from the foregoing that applicant has provided anefficient and smokeless coal heater requiring a minimum of attention,one which need only be started once each season and will operatecontinuously without other attention than the filling of the coal supplyhopper and removing the ash occasionally, and cleaning after eachseasons operation.

The heater is controllable to provide any required quantity of heatbetween settings for maximum and minimum rate of fuel consumption and iseasily regulated to deliver the amount of heat desired, the heateroperating to produce complete combustion of the coal at all settings.

Modifications of the invention may be resorted to without departing fromthe spirit thereof or the scope of the appended claims.

What is claimed is:

l. A heater const'uction comprising a gassing pot, means forcontinuously feeding solid fuel into the pot, a feeding and agitating dum in the pot for advancing the fuel through the pot while it beingconsumed for conducting the ash from the pot, said drum having a centralraised peripheral portion, means for supplying air to the bottom of thepot for combustion purposes, a super-combustion chamber, there being arestricted opening connecting the pot and said chamber, saidsupercombustion chamber having a tortuous passageway with bafflestherein, said gassing pot delivering hot air to the supercoinbustionchamber along with the liberated in the gassing pot, a radiatorsurrounding the supercombustion chamber, said supercombustion chamberemptying into said radiator adjacent to the top thereof through one ormore restricted outlets, a flue connected to the bottom of the radiator,means for conducting a fluid to be heated about the radiator, powermeans for operating the feeding means, the drum and air supplying means,and a single means for regulating the operation of the feeding means,the drum and the air supplying means to vary the rate of fuelconsumption and the rate of su plying air to regulate the temperature ofthe fluid circulated about the radiator.

2. A heater construction comprising a gassing pot, means forcontinuously feeding solid fuel into the pot, a feeding and agitatingdrum in the pot for advancing the fuel through the pot while it is beingconsumed and for conducting the ash from the pot, said drum having acentral raised peripheral portion, means for supplying air to the bottomof the pot for combustion purposes, a supercombustion chamber, therebeing a restricted opening connecting the pot and said chamber, saidsupercombustion chamber having a tortuous passageway with baffiestherein, a radiator surrounding the supercombustion chamber, saidsuper-combustion chamber emptying into said radiator adjacent to the topthereof through one or more restricted outlets, a connected to thebottom of the radiator, means for conducting fluid to be heated aboutthe radiator, power means for operating the feeding means, the drum andthe air supplying means, and a single means for regulating the operationof the feeding means, the drum and the air supplying means to vary theof fuel consumption and the rate of supplying air to regulate thetemperature of the fluid circulated about the radiator.

3. A heater construction comprising a gassing pot, means forcontinuously feeding solid fuel into the pot, a feeding and agitatingdrum in the pot for advancing the fuel through. the pot while it isbeing consumed and for conducting the ash from the pot, means forsupplying air to the bottom of the pot for combustion purposes, asupercornbustion chamber, there being j a restricted opening connectingthe pot and said chamber, said supercombustion chamber having a tortuouspassageway with baffles therein, said gassing pot delivering hot air tothe supercombustion chamber along with the gases liberated in thegassing pot, a radiator surrounding the supercombustion chamber, saidsupercombustion chamber emptying into said radiator adjacent to the topthereof through one or more restricted outlets, a flue connected to thebottom of the radiator, means for conducting fluid to be heated aboutthe radiator, power means for operating the feeding means, the drum andthe air supplying means, and a single means for regulating the operationof the feeding means, the drum and the air supplying means to vary therate of fuel consumption and the rate of supplying air to regulate thetemperature of the fluid circulated about the radiator.

4. A heater construction comprising a gassing pot, means forcontinuously feeding solid fuel into the pot, a feeding and agitatingdrum in the pot for advancing the fuel through the pot while it is beingconsumed and for conducting the ash from the pot, means for supplyingair to the bottom of the pot for combustion purposes, a supercom'oustionchamber, there being a restricted opening connecting the pot and saidchamber, said supercombustion chamber having a tortuous passageway withbaffles therein, a radiator :rounding the supercombustion chamher, saidsupercombustion chamber emptying into said radiator adjacent to the topthereof through one or more restricted outlets, a flue connected to thebottom of the radiator, means for conducting fiuid to be heated aboutthe radiator, power means for operating the feeding means, the drum andthe air supplying means, and a single means for regulating the operationof the feeding means, the drum and the air supplying means to vary therate of fuel consumption and the rate of supplying air to regulate thetemperature of the fluid circulated about the radiator.

5. A heater construction comprising a gassing pot, means forcontinuously feeding solid fuel into the pot, a feeding and agitatingdrum in the pot fOr advancing the fuel through the pot while it is beingconsumed and for conducting the ash from the pot, means for supplyingair to the bottom of the pot for combustion purposes, a supercombustionchamber, there being a restricted opening connecting the pot and saidchamber, said supercombustion chamber having a tortuous passageway withbaiiles therein, a radiator surrounding the supercombustion chamber,said supercombustion chamber emptying into said radiator adjacent to thetop thereof through one or more restricted outlets, a flue connected tothe bottom of the radiator, means for conducting fluid to be heatedabout the radiator, power means for operating the feeding means and thedrum, and a single means for regulating the operation of the feedingmeans and the drum to vary the rate of fuel consumption to regulate thetemperature of the fluid circulated about the radiator.

6. A heater construction comprising a gassing pot, means forcontinuously feeding solid fuel into the pot, a feeding and agitatingdrum in the pot for advancing the fuel through the pot while it is beingconsumed and for conducting the ash from the pot, means for supplyingair to the bottom of the pot for combustion purposes, a supercombustionchamber, there being a restricted opening connecting the pot and saidchamber, said supercombustion chamber having a tortuous passageway withbaffles therein, a radiator surrounding the supercombustion chamber,said supercombustion chamber emptying into said radiator through one ormore restricted outlets, a fiue connected to the radiator, means forconducting fluid to be heated about the radiator, power means foroperating the feeding means and the drum, and a single means forregulating the operation of the feeding means and the drum to vary therate of fuel consumption to regulate the temperature of the fluidcirculated about the radiator.

7. A heater comprising, in combination, a gassing pot, means forcontinuously feeding a stream of solid fuel through said pot, asupercombustion chamber, there being a constricted outlet from thegassing pot into the supercombustion chamber, a radiator, said gassingpot delivering gases to the superoombustion chamber and the latteremptying into the radiator, said radiator enclosing the supercombustionchamber, and a flue connected to the radiator, an outlet for the gasesfrom the supercombustion chamber and the inlet to the flue being atopposite sides of said supercombustion chamber so that the gases in theradiator circulate about the supercombustion chamber in passing to theflue.

8. A heater having, in combination, a gassing pot, means forcontinuously feeding solid fuel through the gassing pot, asupercombustion chamber provided by a refractory casing connected to thegassing pot by a restricted refractory walled opening and in whichsupercombustion chamber the smoke formed by the continuous feeding offresh fuel into the gassing pot will be consumed, and means forconducting the gases delivered from said supercombustion chamber aboutthe outside of said refractory casing to maintain such casing at atemperature at which said smoke will be ignited.

9. A heater having, in combination, a gassing pot, means forcontinuously feeding solid fuel through the gassing pot, asupercombustion chamber in communication with the gassing pot and formedby a refractory casing in which the smoke formed by the continuousfeeding of fresh fuel into the gassing pot will be consumed, and meansfor conveying the gases delivered from the supercombustion chamber aboutthe outside of said refractory casing to maintain said casing at atemperature at which said smoke will be consumed.

10. A heater having, in combination, a gassing pot, means forcontinuously feeding fresh solid fuel therein, means in the gassing potfor advancing the fuel in a stream through combustionzones in the potand finally delivering the ash therefrom, a supercombustion chamber ofrefractory material in communication with the gassing pot for burningthe smoke and gases liberated in the gassing pot, and means forconveying the from the supercornbustion chamber about the outsidethereof.

11. A heater having, in combination, a gassing pot, a radiator having anopening in an end thereof, a removable closure for the opening, and acasing providing a supercombustion chamber enclosed by the radiator,said casing being removably seated on the gassing pot and the bottom ofthe radiator to receive the gases from the pot and empty them into theradiator, said casing being removable through said opening in theradiator.

12. A heater comprising a gassing pot having a fuel feeding andagitating drum in the bottom thereof, means for supplying fuel onto thesurface of the drum, common means for operating the fuel supplying meansand for rotating the drum to feed the fuel through the pot and carryingthe ash therefrom, and means for regulating the rate of supply of thefuel and the rate of rotation of the drum.

13. In a heater, a gassing pot, means for feeding a stream of coal to aninlet therein, a rotary drum in the pot for feeding the coal forwardlyfrom the coal inlet, means for supplying air about the stream of coal,the inner surface of the wall of said pot opposite said inlet being atan inclination to deflect downwardly any ribbon of coal tending tobridge over to said wall, and a secondary rotary drum adjacent said wallfor feeding coals approaching said wall back toward said first drum, theparts being so arranged that the air is fiowable about said secondarydrum and up along said wall.

14. In a heater, a gassing pot, means for feeding a stream of coal to aninlet therein, a rotary drum in the pot for feeding the coal forwardlyfrom the coal inlet, means for supplying air about the stream of coal,the inner surface of the wall of said pot opposite said inlet being atan inclination to deflect downwardly any ribbon of coal tending tobridge over to said wall, and a secondary rotary drum adjacent said wallfor feeding coals approaching said wall back toward said first drum.

15. In a heater, a gassing pot, means for feeding a stream of coal to aninlet therein, a rotary drum in the pot for feeding the coal forwardlyfrom the coal inlet, means for supplying air about the stream of coal,and a secondary rotary drum adjacent the wall of the pot opposite saidcoal inlet for feeding coals approaching said wall back toward saidfirst drum, the parts being so arranged that the air is fiowable aboutsaid secondary drum and up along said wall.

16. In a heater, a gassing pot, means for feeding a stream of coal to aninlet therein, a rotary drum in the pot for feeding the coal forwardlyfrom the coal inlet, means for supplying air about the stream of coal,and a secondary rotary drum adjacent the wall of the pot opposite saidcoal inlet for feeding coals approaching said wall back toward saidfirst drum.

1'7. In a heater, a gassing pot, a secondary combustion chamber incommunication with the gassing pot and adapted to provide a reservoir ofheat for igniting unburned coal gases, means for conveying the gases ofcombustion from said secondary combustion chamber about the outsidethereof, means for feeding coal to said gassing pot, means forpositively feeding air to said gassing pot, said coal and air feedingmeans being synchronized to deliver the coal and air substantially inproper predetermined proportion to produce complete combustion, andmeans for varying the rate of the coal and air feed.

18. Apparatus of the class described, comprising means for feeding solidfuel in a stream, a gassing pot for receiving the fuel therefrom, meansin the gassing pot for conducting the fuel therethrough while beingconsumed and for delivering the ash therefrom, means supplying air tothe bottom of the gassing pot in excess of that required for combustionin the gassing pot, means for conducting the products of combustion, theexcess air and the unburned gases from the gassing pot comprising acasing, there being a constriction between the gassing pot and casing,said casing defining a tortuous passageway, said gassing pot deliveringthe excess air to the casing to be mixed with the gases in saidpassageway, and means for conveying the gases from the said passagewayabout said casing.

19. Apparatus cf the class described, comprising means for feeding solidfuel in a stream, a gassing pot for receiving the fuel therefrom, meansin the gassing pot for conducting the fuel therethrough while beingconsumed and for delivering the ash therefrom, means supplying air tothe bottom of the gassing pot in excess of that required for combustionin the gassing pot, means for conducting the products of combustion andthe unburned gases from the gassing pot comprising a casing, said casingdefining a tortuous passageway, the gassing pot being adapted to deliverfree heated air to be mixed with the gases in said passageway, and meansfor conveying the gases from said passageway about said casing.

20. Apparatus of the class described, comprising means for feeding solidfuel in a stream, a gassing pot for receiving the fuel therefrom, meansin the gassing pot for conducting the fuel therethrough while beingconsumed, means supplying air to the bottom of the gassing pot in excessof that required for combustion in the gassing pot, means for conductingthe products for combustion and the unburned gases from the gassing pot,said means comprising a casing defining a tortuous passageway, saidgassing pot delivering free air to be mixed with the gases in saidpassageway, and means for conveying the gases from said passageway aboutsaid casing.

21. Apparatus of the class described, comprising means for feeding solidfuel in a stream, a

gassing pot for receiving the fuel therefrom, means in the gassing potfor conducting the fuel therethrough while being consumed, meanssupplying air to the bottom of the gassing pot, means for conducting theproducts of combustion and the unburned gases from the gassing pot, saidmeans comprising a casing defining a tortuous passageway, and means forconveying the gases from said passageway about said casing.

22. Apparatus of the class described, comprising means for feeding solidfuel in a stream, a gassing pot for receiving the fuel therefrom, meansin the gassing pot for conducting the fuel therethrough while beingconsumed, means supplying air to the bottom of the gassing pot, meansfor conducting the products of combustion and the unburned gases fromthe gassing pot, said means comprising a casing defining a tortuouspassageway of such length as to be adapted substantially to retard theflow of gases therethrough and thoroughly mix the same therein, andmeans for conveying the gases from said passageway about said casing.

23. In a heater, a radiator, a gassing pot, means for supplying coal ina stream through the pot and ammo means for supplying air thereto, saidair being delivered to said gassing pot in excess of that required forcombustion in said pot, means into which the gassing pot delivers thegases, burned and unburned, along with free air, said means providing areservoir of heat and comprising a core through which the gases pass,said core being mounted in the radiator and delivering the gases ofcombustion thereto, an outlet from said core at one side of the core,and a flue connected to the radiator at another side of the core wherebythe gases of combustion flow about the core to the flue.

24. In a heater, a gassing pot and a fuel feeding and agitating drum inthe bottom portion of the pot by which the fuel is fed while burning,means for feeding a continuous stream of fuel from the rear onto the topof said drum and a grate in front of said drum and extending beneath thedrum to a point at which the ash may be delivered from said gassing potand providing a passage from the burning fuel between the drum and saidgrate whereby the stream of fuel is inverted in passing through saidgassing pot, and means for supplying air about said stream of fuel.

25. A heater comprising, in combination, a foundation, an ash boxprovided therein, a rotary drum over said ash box, a gassing potprovided on said foundation, said drum being at the bottom of said pot,means for supplying solid fuel onto the drum, a casing of refractorymaterial resting on said foundation providing a supercombustion chamberand defining a passageway leading from the pot, and a heat radiatingcasing resting upon the foundation and surrounding the refractorycasing, said supercombustion chamber having an outlet to deliver thegases to said heat radiating casing, said heat radiating casing havingan outlet for the gases in a wall of said heat radiating casing oppositesaid first named outlets whereby the gases delivered from the refractorycasing pass about said refractory casing to the outlet in said heatradiating casing.

26. A heater having, in combination, a gassing pot, means for passing astream of fresh solid fuel through the pot, a supercombustion chamber incommunication with the gassing pot and defined by a casing of refractorymaterial providing a tortuous passage for receiving the gases from thepot, a radiator in which said supercombustion chamber is mounted, saidsupercombustion chamber having an outlet emptying the gases into theradiator, and means on a side of said supercombustion chamber oppositeto said outlet for conveying the gases from the raidator whereby thegases surround the supercombustion chamber.

MARK A. REPLOGLE.

